compilation errors trying to build unzip on cygwin

[Soren <somian08@gmail.com>]

HI. HI!. I've been away from cygwin (and all computer programming
/messing-about) fro several years. Still love Cygwin.

I've gotan archive with the source for `unzip' and I am having trouble
compiling that program. The is the output on the console:

$ make
gcc -c -DASM_CRC -DWIN32 -D__GW32__ -D_LARGEFILE_SOURCE=1
-D_LARGEFILE64_SOURCE=1 -D_FILE_OFFSET_BITS=64 -Wall -O3 -fms-extensions
-mms-bitfi
elds  -fno-exceptions -fomit-frame-pointer -march=i386 -mcpu=i686
-idirafter e:/progra~1/gnuwin32/include -idirafter h:/glibc/include -DUNIXB
ACKUP -DUSE_UNSHRINK -DACORN_FTYPE_NFS -DOS2_EAS -DUSE_CRYPT  -Wall  -o
unzip.o  -O3 -mtune=native -march=native  unzip.c
In file included from win32/w32cfg.h:42,
                 from unzpriv.h:667,
                 from unzip.h:637,
                 from unzip.c:64:
win32/w32cfg.h:91:15: error: expected declaration specifiers or ‘...’
before ‘(’ token
   91 |    extern int setmode(int, int);        /* this is missing in
<fcntl.h> */
      |               ^~~~~~~
win32/w32cfg.h:91:15: error: expected declaration specifiers or ‘...’
before ‘(’ token
   91 |    extern int setmode(int, int);        /* this is missing in
<fcntl.h> */
      |               ^~~~~~~
In file included from unzip.h:637,
                 from unzip.c:64:
unzip.c: In function ‘unzip’:
unzpriv.h:787:22: warning: implicit declaration of function ‘strnicmp’; did
you mean ‘strncmp’? [-Wimplicit-function-declaration]
  787 | #    define STRNICMP strnicmp
      |                      ^~~~~~~~
unzip.c:832:9: note: in expansion of macro ‘STRNICMP’
  832 |     if (STRNICMP(p, LoadFarStringSmall(Zipnfo), 7) == 0 ||
      |         ^~~~~~~~
make: *** [unzip.o] Error 1

The release version of `unzip' is 5.51

Anyone got any ideas? TIA.
-- 
Soren 'tino

He's earthy, he's pithy, he's ...a bit astringent.
Think of him more as a "topical antiseptic" than as a snack
.
    somian08@gmail.com  https://instagram.com/samhain08/
   https://twitter.com/1oh1soren